For the eigenfunction problem, there is a particular polynomial solution of the form \(y(z)=y_{n}(z)\)  which is given by Rodrigues formula [1]};
\(y_{n}(z)=\frac{B_{n}}{\rho (z)}\frac{d^{n}}{dz^{n}}[\sigma ^{n}(z)\rho (z)],\) 
